ALL'M.

134

Pontiff, he said,—" I announce to you a victory over the“ Turk: he draws yearly from the Christians above three“ hundred thousand pieces of gold, paid to him for alum,

“ with which we dye wool of various colours, because none“ is found here, except at the little island of Ischia , for-“ merly called JEnaria, near Puteo/i, and in the cave of“ Vulcan, at Lipari, which being formerly exhausted by“ the Romans is now almost destitute of the substance. I“ have, however, found seven hills so abundant in it, that“ they would be almost enough to supply seven worlds. If“ you will send for workmen, and cause furnaces to be con-“ structed, and the stones to be calcined, you may furnish“ alum to Europe ; and that gain which the Turk used to“ acquire by this article, being thrown inLo your hands, will“ be to him a double loss. Wood and water are both in“ plenty; and you have in the neighbourhood the port of“ Civita Vecchia , where vessels bound to the west may be“ loaded. You can now make war against the Turk : this“ mineral will supply you with the sinews of war, that is“ money, aud, at the same time, deprive the Turk of them.”

The Pope and his cardinals, we are told, consideredthose words of De Castro as the ravings of a madman, orthe mere dreams of astrologers. We are informed, that thefirst neglect of the proposition of De Castro did not dis-hearten him, but he caused representations to be made tothe Pope by various modes: however, eventually, the Pon-tiff employed skilful people, who discovered that the spot towhich De Castro alluded actually contained the mineralproducing alum, and, it is said, of a superior quality to theAsiatic article.

Anciently there was much alum brought from a placecalled Rocca, Roha, or Raha, in Syria , whence this salt issaid to have acquired the name of roche allum. Therewere also anciently very considerable alum-works on amountain in Pliocis, lying close to Ionia: as the mode ofmanufacturing alum at that place is mentioned in the sketchof its history, we subjoin it. The stones found at the top ofthis mountain are calcined in the tire, and then reduced tosand, by being thrown into water; the water with the sandthen boiled with a little more water, the sand becomes liqui-fied,- then falls to the bottom in a cuke, which is preserved;the remainder of the water boiled up again with fresh sand,a fresh cake is procured: the hard and earthy part of thesediment is thrown away as useless; but the cakes beforementioned contain the aluminous substance, which beingagain refined by boiling, is made fit for use.